Reclamation efforts, including but not limited to backfilling, grading, topsoil replacement, and revegetation, on all areas affected by surface impacts incident to an underground coal mine shall occur as contemporaneously as practicable with mining operations, except when such mining operations are conducted in accordance with a variance for concurrent surface and underground mining activities issued under Section 460:20-33-8 of this Chapter. The Department may establish schedules that define contemporaneous reclamation.
(1)Timing of backfilling and grading.(A) Contour mining. Rough backfilling and grading shall follow coal removal by not more than 60 days or 1,500 linear feet. The Department may grant additional time for rough backfilling and grading if the permittee can demonstrate, through a detailed written analysis under Section 460:20-27-10(b) (3), that additional time is necessary;(B) Open pit mining with thin overburden. Rough backfilling and grading shall occur in accordance with the time schedule approved by the Department, on the basis of the materials submitted under Section 460:20-27-10(b) (3), which shall specifically establish in stated increments the period between removal of coal and completion of backfilling and grading.(C) Area strip mining. Rough backfilling and grading shall be completed within 180 days following coal removal and shall not be more than four spoil ridges behind the pit being worked, the spoil from the active pit being considered the first ridge. The Department may grant additional time for rough backfilling and grading. If the permittee can demonstrate, through a detailed written analysis under Section 460:20-27-10(b) (3), that additional time is necessary.Okla. Admin. Code § 460:20-45-37